In history today in 1942 during World War II a Japanese floatplane dropped incendiary bombs on Oregon. In 1947 there was the first case of a computer bug being found: a moth lodged in a relay of a Harvard Mark II computer at Harvard University. In 1956 Elvis Presley appeared on the Ed Sullivan Show for the first time; and in 1993 the Palestine Liberation Organization officially recognized Israel as a legitimate state.

The four-footed friends from Dobrzyń are investigating.

Cyrus: What did you find?

Hili: An ant must’ve walked by here.

In Polish:

Cyrus: Co znalazłaś?
Hili: Chyba jakaś mrówka tu przechodziła.

From Twitter today:

First up a great video of baby lizards.

Horned lizard hatchlings explore their new home today at Mason Mountain Wildlife Management Area in central #Texas.

Another awesomely simple circular motion demo, this time showing that when the centripetal force is removed the object follows a tangent to the circle.Src: YouTube/ISLE Physics pic.twitter.com/H7ZYY2HBdo

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That sea stack in the Eurythmics video is the Old man of Hoy, in the Orkney Islands. 450 feet high. Pretty sure it was greenscreened in the video, somehow.

It was climbed live on BBC TV in 1967, and much later someone walked a high wire between it and the mainland. (I’d be afraid the wire would pull it over, though in reality it’s so massive by comparison that when it does fall it will likely be from its own weight, not outside influences).

BBC Scotland: I watched that too aged 11 along with millions of others – it went on for hours [at least in my memory]. I was glued. Bonnington & co. It must have been a weekend & I suppose it was shuffled with sports bulletins – can’t recall. The live aspect made a big difference of course – like Apollo XI in 1969.

No green screening – I looked it up. The backgrounds are where the principles actually were – Lennox was on top of & standing against that boat for example. They travelled up to the Orkneys & the orchestra worked out of a church [the sort of thing stars do when they have money to waste!]. The only tricks are that weird computerised fuzzing of the background behind Lennox [I don’t think that Lennox is green screen there] AND the bit where there’s multiple Lennoxes AND where both principles appear in the same frame – in those two cases one movie was superimposed over the other.

It’s just across the island from Scapa Flow, actually – something I hadn’t realised till I looked it up on the OS maps on streetmap.co.uk.

It most certainly looks greenscreened, both because the foreground (cliffs etc) are slightly washed-out while the sky background is flickering and there’s a fuzzy join between the two. In fact all the sky, and the waves, have been reduced to monochrome and the contrast increased and it has a lightened edge where it touches any foreground detail such as the cliffs or Annie. Strange.

Mention of the moth in the Mark II allows me to bring up the name of the leader of the project, the remarkable Grace Hopper. She developed the first easily human-readable computing language and the first compiler. She kept trying to retire from her computing role in the US navy, but she was so indispensable that they promoted her to bring her back. She ended up as a rear-admiral.

The Japanese floatplane launched from a submarine that attacked Brookings, Oregon in 1942 was a very daring attack, intended to spread panic. It more or less failed owing to the forest being damp. But it led to some extraordinary followup events.

In the sheep herding film, it looks like there is one dog (white) doing all the herding while several others (black) run around not helping much. I’m guessing the film was made with a marked dog for visibility.

Aside from the one hyperactive white dog, there are several dark dogs which don’t move around so much. Also in the lower right of the field, a larger fuzzy dark object which I take to be the farmer and his shadow. There are also a couple of other humans opening and shutting gates etc.

(It helps to view it full-screen)

The conclusion is sheep are panicky and ornery and will go anywhere you don’t want them to go.

I found it deeply satisfying to see a small handful of sheep scurry off into an empty pen where they obviously were not expected to be. The white dog soon rounded them up and made them join the others. I guess so they will be sheared or eaten. Well, the “eaten” part was not what I found satisfying.

“Tangent” is the only word which actually has two different meanings in mathematics which a few of my slower students find slightly confusing.
(Curves and angles both have tangents. It means two different things.)

To ‘go off at a tangent’ means to deviate from the direct line of discussion. I’d always thought it meant to swerve off at an angle from the straight ahead. But considering its geometric origins, I can only assume that the ‘main course’ is presumed to be a curve and the ‘tangent’ is a ‘straight ahead’ side track.

Actually, it looks like the ball goes off on an angle, and might even be a curved path, not a tangent.

If you stop the GIF at the moment the ball leaves the pan, it’s right side is flush with the grid line (as is the edge of the pan). If it was a tangent, the right side should remain flush with that line. But when it gets to the bottom of the screen, it is about a ball’s width to the left. And I can’t be certain, but it appears to me that it is curving to the left.

Might this be due to ball having some CCW rotation? (Due to its contact with the side of the pan as it goes around.)